GEOLEX database Geologic Unit: Hakatai Usage: Hakatai Shale of Unkar Group of Grand Canyon Supergroup (AZ*) Age: Precambrian* Proterozoic, Middle* Geologic Province: Southern Rocky Mountain region* Areal Extent: AZ(n)* Type Locality: Not designated. Named from Hakatai Canyon, north side of Colorado River, Shinumo quadrangle, Coconino Co., AZ (Noble, 1914). Unit Name History: Name proposed for formation of Unkar group of Grand Canyon series (Noble, 1914). Assigned to Unkar Group of Grand Canyon Supergroup (Elston and Scott, 1976). Overview (Elston, 1989a). Age modified (Elston, 1989b). Note: If you need more information, please contact Nancy Stamm (nstamm@usgs.gov). Asterisks (*) indicate usage by the U.S. Geological Survey. Other usages by state geological surveys. "No current usage" implies that a name has been abandoned or that it has fallen into disuse. Former usage and, if known, replacement name given in parentheses (). Slashes (/) indicate unit name usage violates the 1983 North American Stratigraphic Code. This violation may be explained within brackets ([ ]). U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, USA URL http://ngmdb.usgs.gov/ngmdb/ngm_catalog.ora.html Database project personnel Last modified: 15-Jan-2013